Battery storage startup Antora Energy has successfully raised $550 million in Series C funding, valuing the company at approximately $2.47 billion. The oversubscribed funding round was co-led by G2 Venture Partners and Eclipse, with participation from new investors including Ribbit Capital, Salesforce Ventures, Activate Capital, John Doerr, Westly Group, StepStone Group, and Liberty Mutual Strategic Ventures. The investment will enable Antora to build a second factory to produce its modular batteries for pairing with renewables or grid power, with the company having already doubled manufacturing capacity at its California campus in April 2026. According to recent reports, the Sunnyvale, California company plans to use the capital to scale manufacturing of modular thermal batteries designed for two of the hungriest energy consumers on the planet: heavy industry and data centers.
The Series C round attracted significant institutional backing, with Bill Gates' Breakthrough Energy Ventures participating alongside BlackRock Inc. and Temasek Holdings Pte.'s joint venture Decarbonization Partners. As reported by Investing.com, existing investors including Impact Science Ventures, Trust Ventures, Breakthrough Energy Ventures, and Lowercarbon Capital also participated in the round. Antora had previously raised over $230 million in total funding, including a $150 million Series B in February 2024 that was led by Decarbonization Partners with participation from BlackRock and Temasek. The company also received a $14.5 million SCALEUP grant from ARPA-E in 2024, which is the Department of Energy's venture arm for high-risk, high-reward energy technologies. This latest funding brings Antora's total corporate and project financing to approximately $1 billion, positioning the company for significant expansion across multiple sectors.
According to Investing.com reports, Antora's thermal batteries can discharge firm energy around-the-clock, making them particularly suitable for heavy industrial facilities such as steel or cement plants. The company's batteries operate at 2,400°C (4,352°F) and are designed to store energy for days using less expensive materials compared to lithium-ion batteries. Antora's technology works by taking cheap renewable electricity and using it to heat solid carbon blocks to extreme temperatures, then releasing energy on demand as usable heat and power. This technology is particularly valuable for data centers, which require uninterrupted power that intermittent renewables alone cannot provide, as AI workloads push facility power requirements into unprecedented territory. As reported by recent sources, thermal storage offers a path to decarbonization that doesn't sacrifice uptime, making it crucial for the increasingly power-hungry data center sector.
Just two months ago, Antora began booting up its first commercial-size system: a 5-gigawatt-hour thermal battery at Poet LLC's biofuels plant near Big Stone City, South Dakota. The project, which began commissioning in May 2026, will feature over 200 thermal batteries totaling 5 GWh of storage capacity when completed, representing the largest thermal energy storage project of its kind anywhere in the world. The system will turn cheap wind energy into steam the plant needs to convert corn into ethanol, displacing some of the facility's reliance on coal-fueled boilers. Notably, Antora is pioneering an innovative electricity tariff designed with local utility Otter Tail Power that rewards the company for charging up during periods of surplus local renewable energy production. This structure aims to improve the bottom line for thermal energy systems while ensuring they benefit everyone on the grid, with Antora working with utilities across the country to develop similar rate structures for future projects.
According to Investing.com reports, the funding will accelerate deployment of large-scale projects across the country, enable Antora to establish a second U.S. manufacturing hub, and strengthen the company's domestic supply chain. The company's San Jose, California factory, which the company recently expanded into a three-building manufacturing campus, ranks among the country's largest battery gigafactories. Antora is developing projects in the power sector that would provide the ability for data centers to come online much faster than they otherwise would, with systems potentially five to 10 times the scale of its current 5-GWh South Dakota system. The company is also developing thermophotovoltaic technology to convert heat into electricity, expanding beyond industrial applications into data centers and other energy-intensive sectors. Founded in 2018, Antora has moved from concept to commercial deployment in approximately eight years, with the company declining to share specific details about its growing pipeline of signed agreements with major data center operators and industrial companies.
